1. Field of the Invention
The present invention relates to a traveling course setting system for a moving vehicle, and more particularly to a traveling course setting system for a moving automobile, a moving mobile carrying device in a factory, or a moving vehicle for use in agriculture, civil engineering machinery and the like.
2. Description of the Prior Art
A system for setting the traveling course of a moving vehicle as described above is described in, for example, Japanese Patent Laid-open No. 67476/1984 for detecting a self-position of a moving body by scanning a light beam emitted from the moving body in the circumferential direction centering around the moving body. In this system, retroreflective means Or light reflecting means for reflecting the light beam in precisely the same direction as the incident light are secured at at least three positions apart from the moving body, and the moving body is provided with a light beam source means, a light beam scanning means for scanning a light beam emitted from the light beam source means, and a beam receiving means for receiving light reflected from the light-reflecting means.
In the above system, differential azimuths between adjoining two light-reflecting means centering around the moving body are detected on the basis of received light output of the beam-receiving means, whereby a self-position of the moving body is calculated based on the detected angles and positional information of the light-reflecting means which have been previously set. The moving vehicle bearing the position detecting device travels while detecting the position Of itself so that it does not deviate from the traveling course preset in the work area
In order to make the moving vehicle recognize the work area before commencing actual work, the following means (1) and (2) are employed.
(1) Means for inputting the coordinates and the referential points of the work area to be recognized through an operation of keys on the operator panel or indication by a pen for inputting coordinates on a display.
(2) Means for defining the coordinates of the work area and reference points indicating the work area to be recognized with the position detecting device or the like, by controlling the moving vehicle with radio control or the like to cause it to travel along the outer periphery of the actual work area, or by positioning the moving vehicle at the reference points indicating the work area.
The above-mentioned means have the following problems. In the means (1), the coordinates and/or the reference points must be known, and the input work of the coordinates is cumbersome. In addition, it is too expensive to mount display means on each moving vehicle to simplify the inputting operation. In the means (2), it is time consuming to make the moving vehicle recognize the coordinates and the referential points, and in addition the radio control operation of the moving vehicle is not easy for those other than skilled persons. Further, since the travel position of the moving vehicle (the position at which the moving vehicle exists) becomes harder to recognize from a remote place as the work area becomes wider, it is very difficult to move the moving vehicle along the peripheral outline of the work area unless the operator performs the radio control operation while walking along with the moving vehicle.
As a countermeasure to these problems, for instance, Japanese Patent Laid-open No. 150914/1989 discloses a teaching method of an automatic working vehicle wherein a work area can be taught or changed without relying on human assistance. In this teaching method, the work area is recognized by sequentially moving the working vehicle toward the nearest reflecting means, or the reflecting means having the smallest azimuth with respect to the front direction of the moving vehicle.
If there are obstacles such as trees or ponds in the work area, the actual work area for the working vehicle must be set up so as to detour around these obstacles, which complicates the geometry of the work area. If the work area has a complex geometry, or if the work area is set up in a complex landform, a large number of reflecting means must be located to make the moving vehicle recognize the work area with such teaching method as mentioned above.
In this teaching method, the work area is recognized by sequentially moving the working vehicle toward the nearest reflecting means, or the reflecting means having the smallest azimuth, so there is a problem that the positional condition for disposing the reflecting means is restricted to assure that the Outer periphery of the work area can reliably be recognized.
If there are a lot of reflecting means and those reflecting means are placed irregularly, there is also a problem that, when the steering control is made on the basis of the positional information of the recognized work area or the reflecting means, the selection of the referential reflecting means becomes complicated.